1. Field of the Invention
The present invention relates to an apparatus and a method for processing informational signal. More specifically, the present invention relates to an apparatus and a method for processing informational signal, which converts a first informational signal composed of multiple items of informational data to a second informational signal composed of multiple items of informational data, an apparatus and a method for generating coefficient seed data, which are used in the apparatus and the method for processing informational signal, a program for executing each of the methods, and a medium recording the program thereof.
2. Description of Related Art
Conventionally, a format conversion for converting, for example, a standard definition (SD) signal called as 525i signal to a high definition (HD) signal called as 1050i signal has been proposed. The 525i signal designates an interlace type image signal having 525 lines. The 1050i signal designates an interlace type image signal having 1050 lines.
To achieve the above-described format conversion, a resolution-creating method in which when obtaining pixel data of the 1050i signal from pixel data of the 525i signal, coefficient data of an estimation equation relative to a phase of each pixel of the 1050i signal corresponding to a pixel of the 525i signal is stored in a memory and the pixel data of the 1050i signal is obtained based on that estimation equation using this coefficient data has been proposed.
Japanese Patent Application Laid-Open No.2001-309315 has disclosed that when the image of the aforementioned 1050i signal is displayed on an image display device such as cathode ray tube (CRT) display, liquid crystal display (LCD), plasma display panel (PDP), the coefficient data corresponding to a kind of the image display device is used so as to obtain an image quality fitting to the image display device. For example, when the image display device is of the CRT display, the resolution of the image is set to a normal state. When the image display device is of the LCD, the resolution is set lower than the normal. When the image display device is of the PDP, the resolution is set higher than the normal.
Further, in an apparatus for converting the image signal disclosed in the Japanese Patent Application Laid-Open No.2001-309315, a class to which pixel data of a target position in that HD signal belongs is detected based on multiple items of pixel data of the SD signal located around the target position of the HD signal, thereby acquiring the pixel data of the target position in that HD signal using coefficient data corresponding to this class.
That is, in the apparatus for converting the image signal disclosed in the Japanese Patent Application Laid-Open No.2001-309315, the classification is executed in the same way regardless of the kinds of the image display devices so that classification inadequate to fit to an output characteristic of a used image display device is carried out. This prevents an HD signal adapting to the image display device from being obtained.
An object of the present invention is to make a second informational signal obtained from a conversion of a first informational signal adaptable to an output device for obtaining the output from the second informational signal.